…mode. This is necessary when used together with bindings since controls issue reverse binding updates whenever editing ends, which would add a 'do nothing' undo entry on the stack in cases where nothing changed.

…us animation before starting a new one. This allows e.g. a sheet animating open to 'turn around' and animate right back out. Fixed: if a sheet was closed before it finished animating open, for example by hitting a keyboard equivalent immediately, CPWindow would crash with "Uncaught TypeError: Cannot read property 'sheet' of null".